Provided is a glass direct roving that can achieve good productivity for long glass fiber-reinforced thermoplastic resin pellets, and achieve excellent spinning productivity and good strength of glass fiber-reinforced resin molded articles produced by using long glass fiber-reinforced thermoplastic resin pellets in combination. The glass direct roving includes a plurality of glass filaments bundled together, wherein the filament diameter of the glass filaments, D, is in the range of 17.5 to 21.5 μm, the number of the glass filaments bundled, F, is in the range of 3000 to 7000, the mass of the glass direct roving is in the range of 2450 to 4000 tex, the ignition loss of the glass direct roving, L, is in the range of 0.03 to 0.90%, and the D, F, and L satisfy the following formula (1):

[00001]$\begin{array}{cc}1050\le \left(D^4\times F^{1/4}\right)/\left(1000\times L^{1/6}\right)\le 1640& \left(1\right)\end{array}$

Mineral wool insulation products are provided. The mineral wool insulation includes a plurality of mineral wool fibers and a wax emulsion applied to the mineral wool fibers. The wax emulsion imparts excellent water resistance and thermal performance properties to the mineral wool insulation.

Mineral wool insulation products are provided. The mineral wool insulation includes a plurality of mineral wool fibers and a wax emulsion applied to the mineral wool fibers. The wax emulsion imparts excellent water resistance and thermal performance properties to the mineral wool insulation.

The present invention relates to an alumina fiber having a mass ratio (A/C) of the content (A) of iron oxide as expressed in terms of ferric oxide to the content (C) of titanium oxide of 2 to 121; and a mass ratio (B/C) of the content (B) of calcium oxide to the content (C) of titanium oxide of 0.4 to 14, with a sum total of the content (A) of iron oxide, the content (B) of calcium oxide, and the content (C) of titanium oxide being 0.0170 to 0.1180% by mass.

The present invention relates to inorganic fibres having a composition comprising: 65.7 to 70.8 wt % SiO.sub.2; 27.0 to 34.2 wt % CaO; 0.10 to 2.0 wt % MgO; and optional other components providing the balance up to 100 wt %,
wherein the sum of SiO.sub.2 and CaO is greater than or equal to 97.8 wt %; and the other components, when present, comprise no more than 0.80 wt % Al.sub.2O.sub.3; and wherein the amount of MgO and other components are configured to inhibit the formation of surface crystallite grains upon heat treatment at 1100° C. for 24 hours, wherein said surface crystallite grains comprise an average crystallite size in a range of from 0.0 to 0.90 μm.

The present invention relates to inorganic fibres having a composition comprising: 65.7 to 70.8 wt % SiO.sub.2; 27.0 to 34.2 wt % CaO; 0.10 to 2.0 wt % MgO; and optional other components providing the balance up to 100 wt %,
wherein the sum of SiO.sub.2 and CaO is greater than or equal to 97.8 wt %; and the other components, when present, comprise no more than 0.80 wt % Al.sub.2O.sub.3; and wherein the amount of MgO and other components are configured to inhibit the formation of surface crystallite grains upon heat treatment at 1100° C. for 24 hours, wherein said surface crystallite grains comprise an average crystallite size in a range of from 0.0 to 0.90 μm.

A process for the manufacture of inorganic fibres comprises: (a) selecting a composition and proportion of: (i) silica sand; (ii) lime comprising at least 0.10 wt % magnesia; and (iii) optional additives comprising a source of oxides or non-oxides of one or more of the lanthanides series of elements, or combinations thereof; (b) mixing the silica sand; lime; and optional additives to form a mixture; (c) melting the mixture in a furnace; and (d) shaping the molten mixture into inorganic fibres. The raw materials selection comprises composition selection and proportion selection of the raw materials to obtain an inorganic fibre composition comprising a range of from 61.0 wt % and 70.8 wt % silica; less than 2.0 wt % magnesia; less than 2.0% incidental impurities; and no more than 2.0 wt % of metal oxides and/or metal non-oxides derived from said optional additives; with calcia providing the balance up to 100 wt %; and wherein the inorganic fibre composition comprises no more than 0.80 wt % Al.sub.20.sub.3 derived from the incidental impurities and/or the optional additives.

Methods and apparatus for producing fibers from igneous rock, including basalt include heating igneous rock by electrical conductive coils to achieve an homogenous melt and forming homogenous fibers from the melt.

Methods and apparatus for producing fibers from igneous rock, including basalt include heating igneous rock by electrical conductive coils to achieve an homogenous melt and forming homogenous fibers from the melt.

An alkali-free ultrafine glass fiber formula includes the following components, in mass percentage calculated based on 100 Kg: SiO2: 50% to 65%, Al.sub.2O.sub.3: 10% to 16.5%, CaO: 17% to 28%, MgO: 0.2% to 4.0%, Na.sub.2O and K.sub.2O: 0.1% to 0.8% in total, CeO.sub.2: 0.1% to 0.5%, Li.sub.2O: 0.1% to 0.7%, Fe.sub.2O.sub.3: 0.05% to 0.6%, TiO.sub.2: 0.1% to 1%, and impurities: the balance. In the preparation of alkali-free ultrafine glass fibers, no fluorine and boron-containing raw materials are used, and CeO.sub.2 and Li.sub.2O are introduced, which avoids the use of B.sub.2O.sub.3 and F that have a large impact on the environment, and reduces environmental pollution. A single fiber strength of prepared glass fibers is about 9% higher than that of the traditional E glass fibers, and the comprehensive performance of a prepared glass fiber product is significantly superior than that of the existing E glass fiber product.